A digital ink-based printing system may be used for printing with typical printing inks. Digital ink-based printing processes may include applying fountain solution to a surface of an imaging plate. The imaging plate may be arranged on an outer portion of an imaging cylinder. The imaging cylinder may rotatable for bringing regions of the imaging plate surface to pass adjacent subsystems, including: a dampener for applying fountain solution; a laser for imaging or image-wise vaporization of fountain solution from select regions of the imaging plate; an inker for applying ink to the imaging plate surface; a transfer station from which an ink image is transferred to a printable medium; and a cleaner for removing residue from a surface of the image plate and preparing the surface to begin the process anew. After applying the fountain solution, a high power laser may be used to image-wise vaporize fountain solution from select regions of the surface. The laser may be used to for vaporizing the fountain solution at select surface regions in accordance with digital image data. Ink may be applied by the inker, and may be deposited on regions where fountain solution has been vaporized from the imaging plate. Conversely, ink may be rejected by regions of the imaging plate surface where fountain solution remains. A resulting image is transferred at the transfer station to paper or other suitable media by way of pressure.
The efficiency of ink release from a surface of the imaging plate for transfer to a printable medium such as paper is dependent on presence of an ink release agent on, or in a surface of the imaging plate. For example, the bulk of a silicone imaging plate may include free silicone oil which acts as an ink release agent during the ink transfer step. Because there is a finite amount of free silicone oil in the imaging plate's bulk, ink transfer efficiency will degrade as the silicone oil reserves are depleted. Free silicone oil can be replenished via an external Release Oil Management system. However, a release oil management system adds additional cost and complexity along with potential failure modes associated with release agent layer uniformity.